• 대한조선학회논문집
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• 제61권2호
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• pp.135-142
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• 2024

There is a lot of concern around the world about air pollution from ships. The majority of air pollution from ships comes from fuel combustion. The combustion process produces various air pollutants such as carbon monoxide (CO), carbon dioxide (CO₂), nitrogen oxides (NOx), sulfur oxides (SOx), and particulate matter (PM), each of which has adverse effects on people and is a major environmental problem. To prevent this, the International Maritime Organization (IMO) has strengthened the regulation of pollutant emissions through the Convention for the Prevention of Marine Pollution. This paper discusses the types of air pollutants emitted by ships, their current status, and the latest technologies to reduce emissions of NOx and SOx.

• 한국재료학회지
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• 제18권12호
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• pp.650-654
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• 2008

The emission of carbon dioxide from the burning of fossil fuels has been identified as a major contributor to green house emissions and subsequent global warming and climate changes. For these reasons, it is necessary to separate and recover $CO_2$ gas. A new process based on gas hydrate crystallization is proposed for the $CO_2$ separation/recovery of the gas mixture. In this study, gas hydrate from $CO_2/H_2$ gas mixtures was formed in a semi-batch stirred vessel at a constant pressure and temperature. This mixture is of interest to $CO_2$ separation and recovery in Integrated Coal Gasification (IGCC) plants. The impact of tetrahydrofuran (THF) on hydrate formation from the $CO_2/H_2$ was observed. The addition of THF not only reduced the equilibrium formation conditions significantly but also helped ease the formation of hydrates. This study illustrates the concept and provides the basic operations of the separation/recovery of $CO_2$ (pre-combustion capture) from a fuel gas ($CO_2/H_2$) mixture.

• 환경영향평가
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• 제17권1호
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• pp.67-79
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• 2008

Global warming, which is one of the most serious challenges, has been the subject of intense debate and concern for many scientists, policy-makers, and citizens for at least the past decade. To protect the health and economic well-being of current and future generations, we must reduce our emissions like carbon dioxide. Alternatives to achieve an energy future without serious global warming are to change to clean and renewable sources of energy like the wind, the sun lights, rivers, the biomass, hydrogen, and oceans. To identify some of the key and new environmental impacts associated with renewable energy and hydrogen energy, we set up the new conceptual methodology. Specifically, new identified environmental and health impacts are related with the usage of hydrogen energy. When comparing with fossil fuel, the renewable energies can reduce the release of carbon dioxide when they are used except hydrogen produced from fossil fuel. However, all renewable energy technologies are not appropriate to all applications or locations. Our results suggest that all of alternatives to replace fossil fuel can release the several global and local impacts although they seems to be smaller than the impacts from fossil fuel. Therefore, the quantitative and detail analysis to assess environmental impacts of the alternative energies might be useful to make our decision for the future energy against the global warming.

• KIEAE Journal
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• 제11권3호
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• pp.31-36
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• 2011

People spend most of their time inside buildings recently, so the indoor air quality is one of the most important factors to human health. Furthermore, minimum energy use with proper ventilation systems for pleasant indoor environment is necessary because of energy shortage over the world. The concern to maintain proper indoor air quality at home has been increased, and a proper indoor air quality is continuously requested by the residents. By measuring and analyzing the density fluctuation of $CO_2$ through indoor humidity and testing personal reactions regarding comfort condition, we can obtain a way to effective ventilation. Heat and carbon dioxide emissions from resident's metabolism and construction materials could be the causes of indoor air pollution. If these materials stay indoors for a long time, it could directly influence the resident's health condition with diseases. It also leads massive energy use. Therefore, the way to save energy and to have effective control of indoor ventilation is needed. This study presented the control method of bedroom ventilation by $CO_2$ concentration change and subjective evaluation.

• KIEAE Journal
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• 제10권1호
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• pp.19-24
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• 2010

Modern people are spending most of time in interior area. Indoor air environmental problem is one of the most effective factors influenceable to human health. Furthermore, saving energy and making ventilation system for pleasant indoor environment are necessary when it is faced shortage of energy over the world. In our country's case, it is already imposed that required quantity of air ventilation in buildings is 0.7 times per hour on "The regulation on building engineering system". As on the rise of the interests about Indoor air environment, Heat and Carbon dioxide emissions from User's metabolism, activity, furniture, and construction materials etc. could be the causes of Indoor air pollution. If these materials stays in Indoor air for so long, it could directly influence the user's health condition with a disease. As of building's sterilization improved that raised more mechanical ventilation. It also leads much energy waste in a period of high price of fossil fuel. Therefore, the way that saves energy and effective control of indoor ventilation is urgently needed. So, this study places the purpose on validating volume of indoor ventilation and user's comfortable degree by comparison CO2 emission rate through changing floor temperature.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.300-303
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• 2012

에너지 소비 증가에 따른 이산화탄소 배출로 인한 지구 온난화가 심각하다. 이산화탄소와 산화질소를 배출하지 않으며, 수소로부터 에너지를 생성하는 메커니즘의 개념에 대한 연구를 수행하였다. 수소를 포함하고 있는 수소화물의 한 종류인 소듐 보로하이드라이드($NaBH_4$)와 과산화수소를 반응시켜 수소와 산소 간의 연소 반응을 통한 열에너지 생성 메커니즘에 대한 개념을 도출하였다. 수소화물을 물에 용해시켜 액체 상태로 과산화수소와 반응시킬 경우, 연료에 해당하는 수소화물 수용액과 과산화수소의 질량대비가 0.89일 때 최대 단열 반응 온도가 1795 K까지 상승할 수 있음을 예측하였다.

• Asian Journal of Business Environment
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• 제11권1호
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• pp.39-50
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• 2021

Purpose: This study seeks to establish the environmental damage theory applicable to Kenya. The analysis is based on annual data drawn from World Bank on carbon dioxide emissions (CO2e) and gross domestic product per capita (GDPPC) for Kenya spanning 1963 to 2017. Research Methodology: The study adopts explanatory research design and autoregressive distributed lag model for analysis. Results: The results revealed a coefficient of -0.017 for GDPPC and 0.004 for GDPPC squared indicating that economic growth has negative effect on CO2e in the initial stages of growth but positive effect in the high growth regime with the marginal effect being higher in the initial growth regime. The findings suggest a U-shaped relationship consistent with Brundtland Curve Hypothesis (BCH). Conclusions: The findings emphasize the need for sustainable development path that enables present generations to meet own needs without compromising the capacity of future generations to meet their own. Sustainable development may include, investment in renewable energies like wind, solar and adoption of energy efficient technologies in production and manufacturing. The study concludes that BCH is applicable to Kenya and that developing affordable and effective mechanisms to boost sustainable development implementation is necessary to decrease the anthropogenic impact in the environment without any attendant reduction in the economic growth.

• The Journal of Asian Finance, Economics and Business
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• 제9권2호
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• pp.29-36
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• 2022

This study uses the panel probit model to investigate and evaluate the relationship between exchange rate regimes, political stability, and carbon dioxide during currency crises. To understand currency crisis times, we study a panel dataset of seven South Asian nations that contain annual observations from 1996 to 2020. Furthermore, we created the EMPI exchange market pressure indicator to detect crises. Our results strongly suggested that fixed exchange rate is negatively associated with currency crises, with good regulatory quality and better effective governments. Simultaneously, the floating exchange rate is positively related to the currency crises in those countries where the rule of law has less adequately flowed. However, CO₂, exports, and interest rates are buoyantly associated with crises. The floating exchange rate, the rule of law, exports, and interest rate are associated positively and contribute more prone to the crisis episodes. Negatively associated variables contributed less amid crises episodes: fixed exchange rate regime, government effectiveness, and regulatory quality. Meanwhile, CO₂ has a positive relationship with a currency crisis and contributes more likelihood to the probability of a currency crisis. Countries that adopted the fixed exchange rates with effective governments and regulatory quality faced more minor currency crises.

• 신재생에너지
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• 제19권4호
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• pp.46-52
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• 2023

Methane is the second most emitted greenhouse gas after carbon dioxide. Despite lower emissions than those of carbon dioxide, methane receives significant attention owing to its more than 20-fold higher global warming potential. Consequently, the importance of research on methanotrophic bacteria, microorganisms capable of converting methane gas into high-value materials, is increasingly emphasized. In the case of methanotrophic bacteria, knowledge on episomal plasmids that can be used for genetic engineering remains lacking, which poses significant challenges to the engineering process. The replication origin sequences of natural plasmids within methanotrophic bacteria have been predicted through in silico methods. The basic characteristics of the replication origin, such as a high A/T ratio, repetitive sequences, and proximity to proteins related to replication, have been used as criteria for identifying the replication origin. As a result, a region with a sequence of 18 base pairs repeated eight times could be identified. The putative replication origin sequence thus identified generally takes the form of iterons, but it also possesses unique features such as the length of the gap between iterons and the repetition of identical iteron sequences. This information can be valuable for future design of episomal plasmids applicable to methanotrophs.

• 대한지구과학교육학회지
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• 제16권2호
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• pp.261-275
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• 2023

이 연구의 목적은 탄소중립에 대한 중등 과학 예비 교사의 개념 이해의 수준을 분석하고, 시각화 자료에 나타나는 시선 패턴을 파악하는 것이다. 이 연구의 대상은 중등 과학 예비교사 20명이며, 연구참여자들의 탄소중립에 대한 개념 이해 수준을 구분하고 이에 따른 시선운동의 차이를 분석하였다. 연구 결과는 다음과 같다. 첫째, '2050 탄소중립' 개념을 적용하여 2100년까지의 탄소 배출량과 제거량을 예측하는 모델링 활동을 수행한 결과 연구참여자의 50%가 탄소 배출량이 계속 증가할 것이라는 패턴 매칭을 생각하는 오개념을 갖고 있었다. 또한 연구참여자의 25%는 순 이산화탄소의 배출량과 누적 농도의 인과 관계를 제대로 이해하지 못했다. 둘째, 탄소중립 관련 시각자료에 대한 연구참여자들의 시선운동은 글 영역에 제시된 정보에 크게 영향을 받으며, 그래프의 경우 주로 데이터 영역에 관심이 집중되었다. 그리고 시각적 데이터를 동일한 기능과 범주에 배열했을 때 연구 참가자들은 개념을 설명하는 자료나 왼쪽에 배치된 시각적 데이터에 가장 많은 관심을 보였다. 이는 특정 위치나 순서에 선호가 있음을 의미한다. 개념 이해도가 낮고 요소 간의 인과관계를 제대로 파악하지 못한 연구참여자들은 집중력과 전반적인 시선흐름이 크게 떨어지는 것으로 나타났다. 이러한 결과는 자연재해 및 기후변화를 포함한 탄소중립의 개념적 이해가 시각화 자료에 대한 관심과 참여에 영향이 있음을 나타낸다.